Electronic signatures - which type are acceptable?

The regulatory guidance that relates to the use of electronic signatures in place of wet-ink signatures does not appear to be particularly detailed. The guidance suggests that electronic signatures can be used in place of wet-ink signatures and the 2014 EU Regulation that replaced the electronic signatures directive makes it clear that electronic signatures cannot be refused simply on the basis that they are electronic. However, I'm hearing that sponsors who are getting documents such as protocols electronically signed are having those documents rejected by various regulatory agencies, including MHRA. The anecdotes suggest that it is the electronic signature that is being rejected so I'm trying to get to the root cause.... are only 'qualified electronic signatures' acceptable, for example? And does the qualified certificate have to be issued by any specific body or would DocuSign (for example) be OK? It appears that many companies use electronic signatures for documents within their TMF but it is documents that are submitted to agencies (e.g. the protocol) that are being rejected. If anyone can shed any light on this, that would be great! For example if you've had electronically signed documents rejected, what was the stated reason?

Dear Eldin, unfortunately I cannot contribute to your question. Currently we are using electronic workflows in our Document Management System for the protocol collecting the agreement of the contributing experts. But thereafter we still have a paper signature page for a few selected signatories (the statistician, the sponsor's medically responsible person, the coordinating investigator) - so no reason for refusal by authorities or ethics committees within the scope of your example. However, we may move forward to a completely e-signed protocol. Therefore the topic is very interesting.